/*
 * libusb test library helper functions
 * Copyright © 2012 Toby Gray <toby.gray@realvnc.com>
 *
 * This library is free software; you can redistribute it and/or
 * modify it under the terms of the GNU Lesser General Public
 * License as published by the Free Software Foundation; either
 * version 2.1 of the License, or (at your option) any later version.
 *
 * This library is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
 * Lesser General Public License for more details.
 *
 * You should have received a copy of the GNU Lesser General Public
 * License along with this library; if not, write to the Free Software
 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
 */

#include "libusb_testlib.h"

#include <stdio.h>
#include <stdarg.h>
#include <string.h>
#include <errno.h>
#if !defined(_WIN32_WCE)
#include <sys/types.h>
#include <sys/stat.h>
#include <fcntl.h>
#endif

#if defined(_WIN32_WCE)
// No support for selective redirection of STDOUT on WinCE.
#define DISABLE_STDOUT_REDIRECTION
#define STDOUT_FILENO 1
#elif defined(_WIN32)
#include <io.h>
#define dup _dup
#define dup2 _dup2
#define open _open
#define close _close
#define fdopen _fdopen
#define NULL_PATH "nul"
#define STDOUT_FILENO 1
#define STDERR_FILENO 2
#else
#include <unistd.h>
#define NULL_PATH "/dev/null"
#endif
#define INVALID_FD -1
#define IGNORE_RETVAL(expr) do { (void)(expr); } while(0)

/**
 * Converts a test result code into a human readable string.
 */
static const char* test_result_to_str(libusb_testlib_result result)
{
    switch (result) {
    case TEST_STATUS_SUCCESS:
        return "Success";
    case TEST_STATUS_FAILURE:
        return "Failure";
    case TEST_STATUS_ERROR:
        return "Error";
    case TEST_STATUS_SKIP:
        return "Skip";
    default:
        return "Unknown";
    }
}

static void print_usage(int argc, char ** argv)
{
    printf("Usage: %s [-l] [-v] [<test_name> ...]\n",
        argc > 0 ? argv[0] : "test_*");
    printf("   -l   List available tests\n");
    printf("   -v   Don't redirect STDERR/STDOUT during tests\n");
}

static void cleanup_test_output(libusb_testlib_ctx * ctx)
{
#ifndef DISABLE_STDOUT_REDIRECTION
    if (!ctx->verbose) {
        if (ctx->old_stdout != INVALID_FD) {
            IGNORE_RETVAL(dup2(ctx->old_stdout, STDOUT_FILENO));
            ctx->old_stdout = INVALID_FD;
        }
        if (ctx->old_stderr != INVALID_FD) {
            IGNORE_RETVAL(dup2(ctx->old_stderr, STDERR_FILENO));
            ctx->old_stderr = INVALID_FD;
        }
        if (ctx->null_fd != INVALID_FD) {
            close(ctx->null_fd);
            ctx->null_fd = INVALID_FD;
        }
        if (ctx->output_file != stdout) {
            fclose(ctx->output_file);
            ctx->output_file = stdout;
        }
    }
#endif
}

/**
 * Setup test output handles
 * \return zero on success, non-zero on failure
 */
static int setup_test_output(libusb_testlib_ctx * ctx)
{
#ifndef DISABLE_STDOUT_REDIRECTION
    /* Stop output to stdout and stderr from being displayed if using non-verbose output */
    if (!ctx->verbose) {
        /* Keep a copy of STDOUT and STDERR */
        ctx->old_stdout = dup(STDOUT_FILENO);
        if (ctx->old_stdout < 0) {
            ctx->old_stdout = INVALID_FD;
            printf("Failed to duplicate stdout handle: %d\n", errno);
            return 1;
        }
        ctx->old_stderr = dup(STDERR_FILENO);
        if (ctx->old_stderr < 0) {
            ctx->old_stderr = INVALID_FD;
            cleanup_test_output(ctx);
            printf("Failed to duplicate stderr handle: %d\n", errno);
            return 1;
        }
        /* Redirect STDOUT_FILENO and STDERR_FILENO to /dev/null or "nul"*/
        ctx->null_fd = open(NULL_PATH, O_WRONLY);
        if (ctx->null_fd < 0) {
            ctx->null_fd = INVALID_FD;
            cleanup_test_output(ctx);
            printf("Failed to open null handle: %d\n", errno);
            return 1;
        }
        if ((dup2(ctx->null_fd, STDOUT_FILENO) < 0) ||
            (dup2(ctx->null_fd, STDERR_FILENO) < 0)) {
                cleanup_test_output(ctx);
                return 1;
        }
        ctx->output_file = fdopen(ctx->old_stdout, "w");
        if (!ctx->output_file) {
            ctx->output_file = stdout;
            cleanup_test_output(ctx);
            printf("Failed to open FILE for output handle: %d\n", errno);
            return 1;
        }
    }
#endif
    return 0;
}

void libusb_testlib_logf(libusb_testlib_ctx * ctx,
    const char* fmt, ...)
{
    va_list va;
    va_start(va, fmt);
    vfprintf(ctx->output_file, fmt, va);
    va_end(va);
    fprintf(ctx->output_file, "\n");
    fflush(ctx->output_file);
}

int libusb_testlib_run_tests(int argc,
    char ** argv,
    const libusb_testlib_test * tests)
{
    int run_count = 0;
    int idx = 0;
    int pass_count = 0;
    int fail_count = 0;
    int error_count = 0;
    int skip_count = 0;
    int r, j;
    size_t arglen;
    libusb_testlib_result test_result;
    libusb_testlib_ctx ctx;

    /* Setup default mode of operation */
    ctx.test_names = NULL;
    ctx.test_count = 0;
    ctx.list_tests = false;
    ctx.verbose = false;
    ctx.old_stdout = INVALID_FD;
    ctx.old_stderr = INVALID_FD;
    ctx.output_file = stdout;
    ctx.null_fd = INVALID_FD;

    /* Parse command line options */
    if (argc >= 2) {
        for (j = 1; j < argc; j++) {
            arglen = strlen(argv[j]);
            if ( ((argv[j][0] == '-') || (argv[j][0] == '/')) &&
                arglen >=2 ) {
                    switch (argv[j][1]) {
                    case 'l':
                        ctx.list_tests = true;
                        break;
                    case 'v':
                        ctx.verbose = true;
                        break;
                    default:
                        printf("Unknown option: '%s'\n", argv[j]);
                        print_usage(argc, argv);
                        return 1;
                    }
            } else {
                /* End of command line options, remaining must be list of tests to run */
                ctx.test_names = argv + j;
                ctx.test_count = argc - j;
                break;
            }
        }
    }

    /* Validate command line options */
    if (ctx.test_names && ctx.list_tests) {
        printf("List of tests requested but test list provided\n");
        print_usage(argc, argv);
        return 1;
    }

    /* Setup test log output */
    r = setup_test_output(&ctx);
    if (r != 0)
        return r;

    /* Act on any options not related to running tests */
    if (ctx.list_tests) {
        while (tests[idx].function != NULL) {
            libusb_testlib_logf(&ctx, tests[idx].name);
            ++idx;
        }
        cleanup_test_output(&ctx);
        return 0;
    }

    /* Run any requested tests */
    while (tests[idx].function != NULL) {
        const libusb_testlib_test * test = &tests[idx];
        ++idx;
        if (ctx.test_count > 0) {
            /* Filtering tests to run, check if this is one of them */
            int i;
            for (i = 0; i < ctx.test_count; ++i) {
                if (strcmp(ctx.test_names[i], test->name) == 0)
                    /* Matches a requested test name */
                    break;
            }
            if (i >= ctx.test_count) {
                /* Failed to find a test match, so do the next loop iteration */
                continue;
            }
        }
        libusb_testlib_logf(&ctx,
            "Starting test run: %s...", test->name);
        test_result = test->function(&ctx);
        libusb_testlib_logf(&ctx,
            "%s (%d)",
            test_result_to_str(test_result), test_result);
        switch (test_result) {
        case TEST_STATUS_SUCCESS: pass_count++; break;
        case TEST_STATUS_FAILURE: fail_count++; break;
        case TEST_STATUS_ERROR: error_count++; break;
        case TEST_STATUS_SKIP: skip_count++; break;
        }
        ++run_count;
    }
    libusb_testlib_logf(&ctx, "---");
    libusb_testlib_logf(&ctx, "Ran %d tests", run_count);
    libusb_testlib_logf(&ctx, "Passed %d tests", pass_count);
    libusb_testlib_logf(&ctx, "Failed %d tests", fail_count);
    libusb_testlib_logf(&ctx, "Error in %d tests", error_count);
    libusb_testlib_logf(&ctx, "Skipped %d tests", skip_count);

    cleanup_test_output(&ctx);
    return pass_count != run_count;
}

